Week 4 Worksheet

Learning outcomes

By the end of the session, you should be familiar with:

  • running simple and multiple linear regression in JASP
  • performing a correlation analysis in JASP
  • model building in JASP
  • the interpretation of linear regression coefficients

Intro

We continue where we left off last week, taking further Week 3 Worksheet - Exercise 2 in which we made a scatter plot of inequality by social trust using the Trust & Inequality (trust_inequality.dta) dataset, which can be downloaded from https://cgmoreh.github.io/SOC2069-QUANT/Data/.

In that exercise we simplified the default output by removing the univariate distributions of the variables displayed on the margins and the regression line cutting through the plot. Now, however, we will focus on understanding what that “regression line” is actually telling us.

In later exercises we apply the same techniques to replicate a small part of the regression model reported in Österman (2021) (specifically, model (1) in the summary Table 3, which is presented in more detail in Table A.3 in the Online Supplementary Material accompanying the article)

Finally - probably outside class - you should practice the same linear regression modelling techniques on one of the assignment datasets and research questions.

Exercise 1: From a regression line to regression coefficients

If you haven’t yet downloaded it last week, download the Trust & Inequality (trust_inequality.dta) dataset from https://cgmoreh.github.io/SOC2069-QUANT/Data/

  1. As a first step, create a scatter plot visualising the “relationship” (co-variation, joint distribution, …) between social trust and inequality. This is Exercise 2 from Week 3 - if you need a reminder of how to do it, check Week 3 Worksheet - Exercise 2 or your saved .jasp file containing your workshop analysis from Week 3.

  2. Now let’s dig deeper into the meaning of the regression line by building a simple bivariate linear regression model of social trust as a function of societal inequality (i.e. a model aiming to explain/predict values of social trust in various countries depending on the value of societal inequality in those countries).

To build a linear regression model in JASP, click through the menu options:

\[ \text{Regression} \longrightarrow \text{[Classical] Linear regression} \] In the Linear regression panel, move the “social trust” variable to the \(\text{Dependent Variable}\) box and the “inequality” variable to the \(\text{Covariates}\) box.

The results from the linear regression model will appear in the outputs window on the right.

Questions

  • What is the scatter plot telling us? Note down everything that comes to your mind.

Questions

  • What happens if you add the Region variable to the Split box?
  • Try to interpret what this tri-variate plot is telling us

Exercise 3: Box plots

  1. Create another new descriptive analysis in your JASP session (Descriptives > Descriptive Statistics menu option), to keep your previous analysis above intact on the output page.

  2. We will now check the distribution of “social trust” in different world regions using box plots. Move the trust_pct variable to the Variables box and the Region variable to the Split field. You can resize the output graph so that the Region labels are easier to see.

Questions

  • What is the box plot telling us? Note down everything that comes to your mind. You can use the lecture slides to remind yourself of the information contained in box plots.

Exercise 4: Continue your analysis for Assignment 1

Building on the work you have done in Week 2 Worksheet - Exercise 4, open the dataset you have used to address one of the questions below.

  1. Identify (the) two main variables relevant to the question, perform univariate descriptive statistics, and check their relationship using one of the plots/tabulations practised in the previous exercises above.

  2. Select some other variables of different types and check their association with your main dependent variable using the plots/tabulations practised in the previous exercises above.

Reminder of the research questions to choose from to address in Assignment 1:

  1. Are religious people more satisfied with life?
  2. Are older people more likely to see the death penalty as justifiable?
  3. What factors are associated with opinions about future European Union enlargement among Europeans?
  4. Is higher internet use associated with stronger anti-immigrant sentiments?
  5. How does victimisation relate to trust in the police?
  6. What factors are associated with belief in life after death?
  7. Are government/public sector employees more inclined to perceive higher levels of corruption than those working in the private sector?

For now, choose one question that you find most sympathetic (you don’t need to stick with it for the assignment, but you could if you wanted to!). All of the questions can be answered with at least one of the survey datasets that you downloaded (the “WVS7” or “ESS10”) and often they both contain relevant variables.